Founder Sean Forman began developing the website while working on his Ph.D. dissertation inapplied math andcomputational science at theUniversity of Iowa. While writing his dissertation, he had also been writing articles on and blogging about sabermetrics. Forman's database was originally built from theTotal Baseball series of baseballencyclopedias.[2]
The website went online in April 2000, after first being launched in February 2000 as part of the website for theBig Bad Baseball Annual. It was originally built as a web interface to theLahman Baseball Database, though it now employs a variety of data sources.
In 2004, Forman foundedSports Reference. Sports Reference is a website that came out of the Baseball Reference website. The company wasincorporated as Sports Reference, LLC in 2007.[3] In 2006, Forman left his job as a math professor atSaint Joseph's University to focus on Baseball Reference full-time.[2][1][4]
In February 2009, Fantasy Sports Ventures took a minority stake in Sports Reference, for a "low seven-figure sum".[5]
At the end of April 2021, the site changed a number of identifying names, "discontinuing the use of nicknames that are racially or ethnically influenced" and "names based upon a player's disability", such asChief Bender andDummy Hoy, who are now listed as Charles Bender and Billy Hoy, respectively.[6]
The site has season, career, andminor league records (when available, back to1888) for everyone who has played Major League Baseball, year-by-year team pages, all final league standings, all postseason numbers, voting results for all historic awards such as theCy Young Award andMVP, head-to-head batter vs. pitcher career totals, individual statistical leaders for each season and all-time, managers' career records, the full results of all MLB player drafts,Negro leagues statistics (Baseball Reference added Negro League Statistics to its website in 2021), a baseball encyclopedia (the Bullpen),[7] and box scores and game logs from every MLB game back to1901, among other features.[6]
To compare ballplayers to one-another it offers "Black Ink" and "Gray Ink" tests, which tally a player's dominance and overall productivity against his peers. In 2012, it began to offer Jay Jaffe'sJaffe Wins Above Replacement Score (JAWS) statistic for comparing players of different eras against each other by weighing their performance in the prime as well as their entire career.[8]
Baseball Reference has its own baseball encyclopedia, awiki called "Baseball Reference Bullpen", which can be edited by anyone and is modeled afterWikipedia. As of May 2025,[update] the Baseball Reference Bullpen contains more than 119,000 articles.[7]
There are a number of what the website calls "Frivolities."[12] Examples include:
The Oracle of Baseball, which is no longer active on the website,[13] linked any two players by common teammates in the way the pop culture website "Oracle of Bacon" does.
A page devoted toKeith Hernandez's mustache,[4] which is the only "fictional" page on Baseball Reference.[14]
Although the standard player page notes a given player's favored batting and throwing arms,Paul O'Neill's page adds his kicking leg and a link to a video of the 1989 game when he kicked the ball from the outfield to first base.[16] Likewise, the page forJim Abbott (who was born without a right hand) adds "Fields: Left as well" in addition to him batting and throwing left handed.[17]
Oddibe McDowell's page[21] features his monthly water bill payments from February 2011 to March 2012, which were public record forBroward County, Florida and subsequently were featured in a recurring fashion onDeadspin.[22]
